2004 Dodge Ram 3500 Pickup Owner Manual Diesel - Page 310

310 WHAT TO DO IN EMERGENCIES JUMP-STARTING NOTE: Replacement batteries should both be of equal size to prevent damage to the vehicles charging system. WARNING! To prevent personal injury or damage to clothing, do not allow battery fluid to contact eyes, skin or fabrics. Do not lean over a battery when connecting jumper cables or allow cable clamps to touch each other. Keep open flames or sparks away from battery vent holes. Always wear eye protection when working with batteries. Do not use a booster battery or any other booster source that has a greater than 12 volt system, i.e. do not use a 24 volt power source. Your vehicle is equipped with two 12-volt batteries. If it becomes necessary to use a booster battery, with jumper cables, to start a vehicle's engine because its batteries are discharged, the following procedure should be followed: Set the parking brake and place an automatic transmission in PARK (or NEUTRAL for a manual transmission). Turn off lights, heater and other electrical loads. Observe charge indicator (if equipped) in both batteries. If indicator (if equipped) is light or yellow on either battery, replace that battery.